While lifestyle behaviors (e.g., smoking) are important risk factors for COPD, there is evidence that as much as 37% of the variability in lung function is genetic.13 To explore this, we first sought to identify the genetic effect on the metabolome, detecting significant SNP-metabolite associations in 109 (11%) of the metabolites tested (similar to the 119 of 529 [22%] metabolites previously reported by Shin et al).54 The strongest association was between missense SNP rsrs2147896 in PYROXD2 and N6-methyllysine (p=3.97×10−146). This evidence concerns the gene PYROXD2 and chronic obstructive pulmonary disease.